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1.
J Environ Radioact ; 208-209: 106047, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31526956

RESUMO

As part of an underground gas migration study, two radioactive noble gases (37Ar and 127Xe) and two stable tracer gases (SF6 and PFDMCH) were injected into a historic nuclear explosion test chimney and allowed to migrate naturally. The purpose of this experiment was to provide a bounding case (natural transport) for the flow of radioactive noble gases following an underground nuclear explosion. To accomplish this, soil gas samples were collected from a series of boreholes and a range of depths from the shallow subsurface (3 m) to deeper levels (~160 m) over a period of eleven months. These samples have provided insights into the development and evolution of the subsurface plume and constrained the relative migration rates of the radioactive and stable gas species in the case when the driving pressure from the cavity is low. Analysis of the samples concluded that the stable tracer SF6 was consistently enriched in the subsurface samples relative to the radiotracer 127Xe, but the ratios of SF6 and 37Ar remained similar throughout the samples.


Assuntos
Gases Nobres/análise , Armas Nucleares , Monitoramento de Radiação , Radioatividade , Explosões , Nevada , Medidas de Segurança
2.
J Sci Food Agric ; 97(9): 2706-2713, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27743386

RESUMO

BACKGROUND: The present study aimed to evaluate the correlations among muscle concentrations of three glycometabolic-related hormones (insulin, epinephrine and glucagon), muscle glycolysis and meat quality in representative muscles of either glycolytic or oxidative types. Moreover, the relative glycometabolic-related gene expression was measured. One Western crossbreed DLY (Duroc × (Landrace × Yorkshire)), one crossbreed with half-Chinese native-pig origin DL (Duroc × LiangShan) and one pure Chinese native pig TP (Tibetan pig) were used in the present study. RESULTS: Among the three breeds, DLY had the greatest glucagon and epinephrine (P < 0.01). Compared with DLY, TP and DL had lower lactic acid concentrations, showing lower glycolytic potentials (GP), greater ultimate pH values (P < 0.01) and lower relative expression levels of glycometabolic-related genes (GYS1, PRKAG3 and PKM2). Compared with the glycolytic muscle (musculus longissimus dorsi), oxidative muscle PM (musculus psoas major) had lower glucagon and epinephrine contents, lower GP and better meat quality. The concentration of glycometabolic-related hormones in the muscle had significant correlations with muscle glycolysis, meat pH and lightness. CONCLUSION: The results obtained in the present study imply that glucagon and epinephrine levels could be used to indicate early glycolytic metabolism during postmortem. These findings may be helpful in identifying pork with undesirable quality traits. 2016 Society of Chemical Industry.


Assuntos
Epinefrina/metabolismo , Glucagon/metabolismo , Insulina/metabolismo , Carne/análise , Músculo Esquelético/metabolismo , Suínos/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Cruzamento , Glicólise , Músculo Esquelético/química , Oxirredução , Suínos/genética , Suínos/crescimento & desenvolvimento
3.
Stand Genomic Sci ; 10: 62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26380647

RESUMO

Bacillus thuringiensis is the most widely used biological pesticide in the world. It belongs to the Bacillus cereus sensu lato group, which contains six species. Among these six species, B. thuringiensis, B. anthracis, and B. cereus have a low genetic diversity. B. thuringiensis strain HD521 shows maroon colony which is different from most of the B. thuringiensis strains. Strain HD521 also displays an ability to inhibit plant sheath blight disease pathogen (Rhizoctonia solani AG1 IB) growth and can form bipyramidal parasporal crystals consisting of three cry7 genes. These crystals have an insecticidal activity against Henosepilachna vigintioctomaculata larva (Coleoptera). Here we report the complete genome sequence of strain HD521, which has one chromosome and six circular plasmids.

4.
J Fish Biol ; 75(9): 2352-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738692

RESUMO

Two populations of Przewalski's naked carp Gymnocypris przewalskii, 30 individuals per population, were screened for 10 microsatellite loci. Moderate allele variation was found in these loci with two to eight alleles per locus. The expected and observed heterozygosity ranged from 0.019 to 0.805 and from 0.160 to 0.575, respectively.


Assuntos
Carpas/genética , Variação Genética , Genética Populacional , Repetições de Microssatélites , Alelos , Animais , China , Análise de Sequência de DNA
5.
J Food Sci ; 73(1): T16-20, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18211378

RESUMO

Anticarcinogenic activity of medicinal herbs (Artemisia capillaris, Taxus cuspidata, Anthriscus sylveatris, and Curcuma longa) was examined for 7,12-dimethylbenz[a]anthracene (DMBA)-induced mouse skin carcinogenesis. Four types of solvent fractions (hexane, chloroform, ethyl acetate, and butanol) were prepared from the methanolic extract of medicinal herbs. The cytotoxicity and anticarcinogenic activities of solvent fractions were examined for mouse leukemia L1210 cancer cells and for female ICR mouse epidermal carcinogenesis induced by DMBA, respectively. The chloroform fraction of Artemisia capillaris, Taxus cuspidata, and Anthriscus sylveatris was more toxic to L1210 cells than other solvent fractions. The chloroform fraction of Artemisia capillaris markedly reduced the number of tumors/mouse and tumor incidence relative to that of other medicinal herbs tested. Major active chemical constituents in the chloroform fraction of Artemisia capillaries were found to be camphor, 1-borneol, coumarin, and achillin when analyzed by TLC and GC-MS. These results suggest that Artemisia capillaris was the most effective anticarcinogenic medicinal herb for DMBA-induced mouse epidermal carcinogenesis among 4 medicinal herbs tested, and the effect might be attributed to chemical compounds of camphor, 1-borneol, coumarin, and achillin.


Assuntos
Anticarcinógenos/farmacologia , Artemisia/química , Fitoterapia , Extratos Vegetais/farmacologia , Neoplasias Cutâneas/prevenção & controle , 9,10-Dimetil-1,2-benzantraceno/antagonistas & inibidores , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Canfanos/análise , Canfanos/farmacologia , Cânfora/análise , Cânfora/farmacologia , Testes de Carcinogenicidade , Carcinógenos/antagonistas & inibidores , Carcinógenos/toxicidade , Clorofórmio , Cumarínicos/análise , Cumarínicos/farmacologia , Modelos Animais de Doenças , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/análise , Distribuição Aleatória , Sesquiterpenos/análise , Sesquiterpenos/farmacologia , Neoplasias Cutâneas/epidemiologia
7.
J Am Chem Soc ; 124(41): 12094-5, 2002 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-12371839

RESUMO

In this communication, we experimentally report, for the first time, that the MnO nanoclusters with cluster diameters of 5-10 nm show a ferromagnetic behavior with a phase transition from ferromagnetic to paramagnetic phases at 27 K even though their bulk phase is antiferromagnetic. We observed large coercivities up to 9500 Oe and a large remanence of 1.72 emu/g at 2 K, which are typically observed values for ferromagnetic materials. Although it is not clear, this abnormal ferromagnetic behavior of MnO nanoclusters may arise from cluster size effects.

8.
Artigo em Inglês | MEDLINE | ID: mdl-11088874

RESUMO

Spatiotemporal chaos control by applying local feedback injections is investigated analytically. The influence of gradient force on the controllability is investigated. It is shown that as the gradient force of the system is larger than a critical value, local control can reach very high efficiency to drive the turbulent system of infinite size to a regular target state by using a single control signal. The complex Ginzburg-Landau equation is used as a model to confirm the above analysis, and a four-wave-mixing mode is revealed to determine the dynamical behavior of the controlled system at the onset of instability.

10.
11.
12.
Phys Rev Lett ; 76(16): 3017-3020, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10060849
17.
Phys Rev Lett ; 74(2): 318-321, 1995 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-10058358
18.
J Nucl Biol Med (1991) ; 38(4): 540-4, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7786915

RESUMO

The distribution of 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI), assessed by single photon emission computed tomography (SPECT) was compared to the distribution of 2-[18F]-2-deoxy-D-glucose ([18F]FDG) assessed with positron emission tomography (PET) under fasting conditions, in 21 patients with coronary artery disease (CAD) and severe left ventricular dysfunction in order to evaluate the potential usefulness of SPECT/99mTc-MIBI for the identification of viable myocardium. Stress and rest SPECT/99mTc-MIBI studies were scored based on the percent of 99mTc-MIBI uptake defined by semi-quantitative circumferential-profile analyses. PET metabolic studies with [18F]FDG under fasting conditions, were adopted as a standard of viability. The results of the comparison of 99mTc-MIBI and [18F]FDG distribution showed that among the segments with stress hypoperfusion, [18F]FDG uptake was present in 95% of the segments that had > 40% of the peak tracer uptake at the rest SPECT/99mTc-MIBI study. [18F]FDG uptake was also present, however, in 25% of the segments that had < 40% uptake at the rest SPECT/99mTc-MIBI scintigraphy. We conclude that in patients with CAD the pattern of 99mTc-MIBI distribution appears to underestimate the extent of viable myocardium but only in those regions that are very severely hypoperfused.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Desoxiglucose/análogos & derivados , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Idoso , Feminino , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade
19.
Phys Rev Lett ; 73(25): 3435-3438, 1994 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-10057380
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